The core of the proposed Program Project on The Global Burden of Disease in Aging population will play a central role in coordinating the activities of the eight research teams, in terms of administrative, data and methodological needs. The core will be based at the Harvard Burden of Disease Unit at the Harvard Center for Population and Development Studies and will have three main functions. First, the administrative component of the core will provide support to the eight research projects by facilitating interactions between the project leaders, encouraging exchanges between the investigators in the program and public health professionals working on related issues at the World Health Organization, preparing and coordinating reports and publications, preparing and coordinating program reports and publications, and overseeing the overall program budget. Second, the data component of the core will create a Global Databank, using the prototype and software developed by Harvard-MIT Data Center. The Global Databank will contain all data collected, analyzed, generated, and used by this program, as well as the software packages that will be developed in the course of the program. All internet users will have access to the Global Databank but some parts of it will have recruited aces. The Databank will also be connected "virtually", through software in development of the Virtual Data Center at Harvard and MIT, to other global databanks with socioeconomic, demographic and health data. Third, the include a methods component for the development, adaptation, and refinement of statistical methods that will be useful to every component of the program. The methods core will develop a multiple imputation method for dealing with missing data, and a method based on simulation for improving the presentation of results in a substantively meaningful way, including ranges of uncertainty. Both of these methods will be developed into software packages that will be widely available for use through the internet.